Moldy Corks?

[lhunkele]

I'm using natural corks. I've been sanitizing the corks in a sealed zip-loc bag with an open bottle of k-meta in the bag for 1-hr or so before bottling. I store the wine on it's side in a wine rack in the basement. I've only been making wine since last fall, so nothing is more than 6-month old, but it appears as though (some?) of the corks are moldy? I'm not noticing any off-flavors with the wine.

Any suggestions? What kind of corks do you use, how do you sanitize?

 

[Wade E]

Its most likely not the cork unless you are seeing a bleed through of wine through your corks. Its most likely that you have way too much humidity in your cellar which lots of people will have including me so I run a dehumidifier in the bad summer months. If I wasnt the humidity would be almost 100% in there. It should be kept rigt at 70%!!!!! Much more and youll have mold problems and too much less and your corks will dry out and yes thats even if you have the bottle tipped over. Its the outside that dries out and starts cracking letting your win e breathe too much comprising your wine.

 

[lhunkele]

Thanks Wade. I put a humidistat downstairs to check the humidity and can also run a dehumidifier if need be. Just for clarification, the mold (if that's what it is) is on the inside portion of the cork, and an additional note, all the wines I have bottled I have also put the foils on around the neck/cork of the bottle...

 

[Runningwolf]

I also had the same issue until I started running my dehumidifier.

 

[Wade E]

Can you show us a pic of this mold. On the inside like between the wine and the cork or between the cork and the bottle top? If between bottle and cork is it white as if so that may just be paraffin wax which is usually applied to most corks to ease in the corking process.

 

[lhunkele]

Humidistat is reading close to 75%, dehumidifier is running, thank you, I hadn't thought about that...

I have the cork but now that it's dry you really can't see anything. I'll try to get a photo on the next bottle we open. It's on the bottom of the cork, the flat part of the cork that is in contact with the wine. I thought I had noticed something before, but let it go, then last night I mentioned and showed it to my husband and he thought it was mold too...

 

[Wade E]

Yeah, we'll need to see a pic but cant see how the inside of the cork could get moldy and not have the wine spoil.

 

[Ignoble Grape]

Okay, I'm going to refresh this thread. Happened to me for a rose I opened last night. Bottled around 6 months ago. Wine was fine, cork was not. You can see that the mold hasn't reached the wine part, yet. I'm going to open another bottle and see if it's a unique occurance, or whether I might have a problem.

Thoughts? Is this a humidity or a sanitation issue?

 

[stickman]

Well that's a new one on me, I've been doing this for 29 years and haven't seen that before. I'm suspicious of the corks, the wine stain goes too far up the cork for only 6 months in the bottle. The cork can easily get contaminated with wine during the corking process, which theoretically could support mold growth, just never seen it like that. Were the corks purchased from a reputable supplier?

 

[Ignoble Grape]

Well that's a new one on me, I've been doing this for 29 years and haven't seen that before. I'm suspicious of the corks, the wine stain goes too far up the cork for only 6 months in the bottle. The cork can easily get contaminated with wine during the corking process, which theoretically could support mold growth, just never seen it like that. Were the corks purchased from a reputable supplier?

I don't remember where I got the corks - most likely Amazon. I need to keep better track of those types of details. If it is the corks, that would be a relief. I just bottled 4 cases using corks from the brew supply shop, but composite like the above. Will be bottling my high-quality wine in a few months, perhaps I should invest in the solid synthetics for that one...

 

[cmason1957]

You didn't happen to soak those corks in some type of sanitizer before inserting them, did you?? I agree for 6 months in the bottle that seems like a lot of seepage of wine up.

 

[Ignoble Grape]

You didn't happen to soak those corks in some type of sanitizer before inserting them, did you?? I agree for 6 months in the bottle that seems like a lot of seepage of wine up.

I did, potassium metabisulphite solution. ??

 

[cmason1957]

I did, potassium metabisulphite solution. ??

I almost would have guessed that. I used to soak corks, but then had one time when the corks leaked wine out the top. I believe that is why the wine seems to have wicked up further than might be expected in 6 months and maybe lead to the mold.

I don't have a good explanation for what happened, but nowadays, I insert them dry or, if my wife is watching, give them a very sparse squirt of K-Meta solution. I know many folks use a corkador, which is to place them in something inside a bucket with K-meta solution and let the sulpher rise over them.

 

[Ignoble Grape]

Corcador - how pretentious. Luv it. Thanks!

 

[bstnh1]

Maybe it's just me, but I don't see a lot of seepage on that cork. It's a chamfered cork, so the last few mm don't even contact the bottle.